Gravel makes creek good for native species

By SAMANTHA TIPLER

Klamath Falls Herald and News

Published:October 15, 2013 1:05PM

Gravel is used to provide spawning grounds for trout.

KLAMATH FALLS, Ore. (AP) — Gravel spit out of the back of the dump truck in a giant arc, landing on the far side of Crooked Creek. The angle changed, sending the gravel to the center and near side. Back and forth it went, the small rocks splashing into the water.

Once the load was emptied, Nell Kolden, restoration director with the Klamath Basin Rangeland Trust, waded into the creek and raked the gravel, smoothing the piles across the bottom of the waterway.

She, along with Christie Adelsberger, restoration specialist with the rangeland trust, were working to improve spawning grounds for native redband trout. The rangeland trust works with landowners and the U.S. Fish and Wildlife Service to improve habitat for fish species in the Klamath Basin.

“It’s pretty cool to be able to come out, put the gravel in and come out a month or two later and actually be able to see that the fish are using it,” Kolden said.

Redband trout are native to the Wood River and Crooked Creek, one of its tributaries. Crooked Creek is a place where the fish may have spawned in the past, but its muddy bottom does not work well for redds — the depression where the trout lay their eggs.

The gravel the Klamath Basin Rangeland Trust installed in Crooked Creek will be prime spawning habitat for the redbands.

“The more we can help them, the more they can compete with the brook trout and brown trout, two non-native trout species people fish,” Kolden said. “But we want to give the natives a leg up so they can have the chance to compete with the non-natives.”

The bottom of Crooked Creek is deep, fine-sediment mud — not ideal for spawning redband trout.

“It smothers their eggs,” Adelsberger said. “Basically it doesn’t allow oxygen to get to those eggs and they die.”

Gravel, made of larger pieces with bigger spaces in between, allows the oxygen to get to the eggs.

“They have flow-through and allow the oxygen exchange with the water,” Adelsberger said, which helps the redbands.

“They require these gravel additions,” she continued. “Typically that would be a natural habitat available to them. This is an enhancement to help their spawning efforts.”

“We basically try to spread out the gravel in a way that will make it available for lots of different redbands to spawn there,” Kolden said. “They’ll start spawning in the next couple months. We’ll be able to come out and see their big redds — where they flush out the gravel and make big depressions where they lay their eggs.”

At the Crooked Creek project the rangeland trust also installed tree roots, or wood additions, at each bend the creek takes through the pasture owned by Gerry and Mark Hawkins.

Kolden said wood debris has been removed from many Oregon waterways because people thought rivers and streams looked cleaner without them. But the removal has led to problems, and groups like the rangeland trust are working to put wood back into the river.

“You put one piece of wood in there and all of a sudden the water will start moving differently, maybe scour out a pool,” Kolden said. “You get a lot more habitat complexity by adding wood.”

For the redband trout, the large tree roots in Crooked Creek will provide natural cover from predators.

“They provide a lot of little tiny spaces for juvenile fish to hang out,” Kolden said. “The juveniles can rest in there. They can be protected from whatever predators are around. They’re not just stuck in this open water with birds and other fish.”

Adding wood and tree roots helps stabilize the bank and encourages more vegetation to grow. Often in places like the Crooked Creek project, cattle eat the vegetation, leaving the stream bank nearly bare and ripe for erosion. The more a stream bends, the more it can eat into a landowner’s field.

“A landowner doesn’t want to lose a big portion of his property. If this keeps moving outwards, all of a sudden he’s lost an acre of his pasture. That’s something that doesn’t make anybody happy,” Kolden said pointing to the outward side of a bend in the creek. “This is a good way to figure out how can we work with them to make sure they’re needs are met, and how can we also meet the needs of the fish so they don’t lose the habitat that does exist here.”